It is well known that, an overload problem possibly occurs in actual operations of networks for wireless communication systems such as a universal mobile telecommunications system (UMTS). In the case of overloading, in order to guarantee the quality of service (QoS) for currently connected users, new users are usually restricted from accessing the network, or relocated to frequency layers or radio access technologies (RATs) different from the current service cell.
The relocation of the users is mainly realized through a radio resource control (RRC) connection setup message or an RRC connection reject message during an RRC connection setup process, or realized through an RRC connection setup/release message during an RRC connection release process.
In the current technical solution, user equipment (UE) carries a measurement result of the frequency layer used or unused by the UE in an RRC connection request message to be sent to the network side. Therefore, when the network side needs to make a relocation indication for the UE, the network side may indicate the UE to be relocated to an appropriate frequency layer according to the measurement result reported by the UE.
The network side may not only indicate the UE to be relocated to different frequency layers, but also indicate the UE to be relocated to different RATs. However, the current relocation indication for the RAT in the UMTS is a blind indication. That is to say, the current UE does not measure the RAT, and thus does not have any RAT related measurement result that can be sent to the network side. Therefore, the network side has no support of the RAT measurement data when performing the RAT relocation indication.
In order to solve the problem about RAT blind indication in relocation, the UE is configured to perform an inter radio access technology (IRAT) handover measurement once before sending the RRC connection request message, and carry the measurement result in the RRC connection request message for being reported to the network side.
During the implementation of the disclosure, the inventor(s) found that the prior art has at least the following technical problems. Though the prior art may eliminate the RAT blind indication in relocation, the following two problems occurs.
First, the processing in the prior art may affect the call setup performance of the UE. The reason is that, during the time period from initiating a call setup request each time by the UE to sending an RRC connection request message to a base station (BS), the UE must perform an IRAT measurement, which inevitably extends the call setup delay.
Second, the UE usually performs unnecessary measurements and reports. The UE has no idea whether the network side relocates the UE after a call is initiated, so the UE needs to make a measurement each time before sending the RRC connection request message, and report a measurement result. Generally, the network side does not need to frequently relocate the UE, and thus the UE has made many unnecessary measurement and report tasks.
In addition, the requirements of automatic network configuration and optimization are proposed in a long term evolution (LTE) system. In order to support the automatic network optimization, the UE needs to perform some additional measurements to provide the measurement data to the network side, so as to enable the network side to perform data accumulation for network configuration and optimization. Moreover, in order to obtain the measurement data of the network in a complicated environment, the measurement and report triggered by the UE based on certain information are also needed.
In view of the above, the wireless communication system requires the UE to perform more information measurement, but currently no measurement control solution is able to reduce the impact of the measurement on the performance of the UE to the utmost extent while ensuring that the UE provides the measurement result to the network side in time.